<?php // $Id: setuplib.php,v 1.22.2.4 2008/01/20 17:58:06 skodak Exp $ 
	  // These functions are required very early in the Moodle 
	  // setup process, before any of the main libraries are 
	  // loaded.


/**
 * Simple class
 */
class object {};


/**
 * Initializes our performance info early.
 *
 * Pairs up with get_performance_info() which is actually
 * in moodlelib.php. This function is here so that we can 
 * call it before all the libs are pulled in. 
 *
 * @uses $PERF
 */
function init_performance_info() {

	global $PERF, $CFG, $USER;
  
	$PERF = new Object;
	$PERF->dbqueries = 0;   
	$PERF->logwrites = 0;
	if (function_exists('microtime')) {
		$PERF->starttime = microtime();
		}
	if (function_exists('memory_get_usage')) {
		$PERF->startmemory = memory_get_usage();
	}
	if (function_exists('posix_times')) {
		$PERF->startposixtimes = posix_times();  
	}
	if (function_exists('apd_set_pprof_trace')) {
		// APD profiling
		if ($USER->id > 0 && $CFG->perfdebug >= 15) {
			$tempdir = $CFG->dataroot . '/temp/profile/' . $USER->id; 
			mkdir($tempdir);
			apd_set_pprof_trace($tempdir);
			$PERF->profiling = true;
		}
	}
}

/**
 * Function to raise the memory limit to a new value.
 * Will respect the memory limit if it is higher, thus allowing
 * settings in php.ini, apache conf or command line switches
 * to override it
 *
 * The memory limit should be expressed with a string (eg:'64M')
 *
 * @param string $newlimit the new memory limit
 * @return bool
 */
function raise_memory_limit ($newlimit) {

	if (empty($newlimit)) {
		return false;
	}

	$cur = @ini_get('memory_limit');
	if (empty($cur)) {
		// if php is compiled without --enable-memory-limits
		// apparently memory_limit is set to ''
		$cur=0;
	} else {
		if ($cur == -1){
			return true; // unlimited mem!
		}
	  $cur = get_real_size($cur);
	}

	$new = get_real_size($newlimit);
	if ($new > $cur) {
		ini_set('memory_limit', $newlimit);
		return true;
	}
	return false;
}

/**
 * Converts numbers like 10M into bytes.
 *
 * @param mixed $size The size to be converted
 * @return mixed
 */
function get_real_size($size=0) {
	if (!$size) {
		return 0;
	}
	$scan['MB'] = 1048576;
	$scan['Mb'] = 1048576;
	$scan['M'] = 1048576;
	$scan['m'] = 1048576;
	$scan['KB'] = 1024;
	$scan['Kb'] = 1024;
	$scan['K'] = 1024;
	$scan['k'] = 1024;

	while (list($key) = each($scan)) {
		if ((strlen($size)>strlen($key))&&(substr($size, strlen($size) - strlen($key))==$key)) {
			$size = substr($size, 0, strlen($size) - strlen($key)) * $scan[$key];
			break;
		}
	}
	return $size;
}

/**
 * Create a directory.
 *
 * @uses $CFG
 * @param string $directory  a string of directory names under $CFG->dataroot eg  stuff/assignment/1
 * param bool $shownotices If true then notification messages will be printed out on error.
 * @return string|false Returns full path to directory if successful, false if not
 */
function make_upload_directory($directory, $shownotices=true) {

	global $CFG;

	$currdir = $CFG->dataroot;

	umask(0000);

	if (!file_exists($currdir)) {
		if (! mkdir($currdir, $CFG->directorypermissions)) {
			if ($shownotices) {
				echo '<div class="notifyproblem" align="center">ERROR: You need to create the directory '. 
					 $currdir .' with web server write access</div>'."<br />\n";
			}
			return false;
		}
	}

	// Make sure a .htaccess file is here, JUST IN CASE the files area is in the open
	if (!file_exists($currdir.'/.htaccess')) {
		if ($handle = fopen($currdir.'/.htaccess', 'w')) {   // For safety
			@fwrite($handle, "deny from all\r\nAllowOverride None\r\n");
			@fclose($handle);
		}
	}

	$dirarray = explode('/', $directory);

	foreach ($dirarray as $dir) {
		$currdir = $currdir .'/'. $dir;
		if (! file_exists($currdir)) {
			if (! mkdir($currdir, $CFG->directorypermissions)) {
				if ($shownotices) {
					echo '<div class="notifyproblem" align="center">ERROR: Could not find or create a directory ('. 
						 $currdir .')</div>'."<br />\n";
				}
				return false;
			}
			//@chmod($currdir, $CFG->directorypermissions);  // Just in case mkdir didn't do it
		}
	}

	return $currdir;
}

/**
 * This function will introspect inside DB to detect it it's a UTF-8 DB or no
 * Used from setup.php to set correctly "set names" when the installation
 * process is performed without the initial and beautiful installer
 */
function setup_is_unicodedb() {

	global $CFG, $db, $INSTALL;

	$unicodedb = false;
	
	// Calculate $CFG->dbfamily
	$dbfamily = set_dbfamily();

	switch ($dbfamily) {
		case 'mysql':
			$rs = $db->Execute("SHOW LOCAL VARIABLES LIKE 'character_set_database'");
			if ($rs && !$rs->EOF) { // rs_EOF() not available yet
				$records = $rs->GetAssoc(true);
				$encoding = $records['character_set_database']['Value'];
				if (strtoupper($encoding) == 'UTF8') {
					$unicodedb = true;
				}
			}
			break;
		case 'postgres':
		/// Get PostgreSQL server_encoding value
			$rs = $db->Execute("SHOW server_encoding");
			if ($rs && !$rs->EOF) { // rs_EOF() not available yet
				$encoding = $rs->fields['server_encoding'];
				if (strtoupper($encoding) == 'UNICODE' || strtoupper($encoding) == 'UTF8') {
					$unicodedb = true;
				}
			}
			break;
		case 'mssql':
		/// MSSQL only runs under UTF8 + the proper ODBTP driver (both for Unix and Win32)
			$unicodedb = true;
			break;
		case 'oracle':
		/// Get Oracle DB character set value
			$rs = $db->Execute("SELECT parameter, value FROM nls_database_parameters where parameter = 'NLS_CHARACTERSET'");
			if ($rs && !$rs->EOF) { // rs_EOF() not available yet
				$encoding = $rs->fields['value'];
				if (strtoupper($encoding) == 'AL32UTF8') {
					$unicodedb = true;
				}
			}
			break;
	}
	return $unicodedb;
}

/**
 * This internal function sets and returns the proper value for $CFG->dbfamily based on $CFG->dbtype
 * It's called by preconfigure_dbconnection() and at install time. Shouldn't be used
 * in other places. Code should rely on dbfamily to perform conditional execution
 * instead of using dbtype directly. This allows quicker adoption of different
 * drivers going against the same DB backend.
 *
 * This function must contain the init code needed for each dbtype supported.
 *
 * return string dbfamily value (mysql, postgres, oracle, mssql)
 */
function set_dbfamily() {

	global $CFG, $INSTALL;

	// Since this function is also used during installation process, i.e. during install.php before $CFG->dbtype is set.
	// we need to get dbtype from the right variable 
	if (!empty($INSTALL['dbtype'])) {
		$dbtype = $INSTALL['dbtype'];
	} else {
		$dbtype = $CFG->dbtype;
	}

	switch ($dbtype) {
		case 'mysql':
		case 'mysqli':
			$CFG->dbfamily='mysql';
			break;
		case 'postgres7':
			$CFG->dbfamily='postgres';
			break;
		case 'mssql':
		case 'mssql_n':
		case 'odbc_mssql':
			$CFG->dbfamily='mssql';
			break;
		case 'oci8po':
			$CFG->dbfamily='oracle';
			break;
	}

	return $CFG->dbfamily;
}

/**
 * This internal function, called from setup.php BEFORE stabilishing the DB
 * connection, defines the $CFG->dbfamily global -by calling set_dbfamily()-
 * and predefines some constants needed by ADOdb to switch some default
 * behaviours.
 *
 * This function must contain all the pre-connection code needed for each
 * dbtype supported.
 */
function preconfigure_dbconnection() {

	global $CFG;

/// Define dbfamily
	set_dbfamily();

/// Based on $CFG->dbfamily, set some ADOdb settings
	switch ($CFG->dbfamily) {
		/// list here family types where we know
		/// the fieldnames will come in lowercase
		/// so we can avoid expensive tolower()
		case 'postgres':
		case 'mysql':
		case 'mssql':
			define ('ADODB_ASSOC_CASE', 2);
			break;
		case 'oracle':
			define ('ADODB_ASSOC_CASE', 0); /// Use lowercase fieldnames for ADODB_FETCH_ASSOC
											/// (only meaningful for oci8po, it's the default
											/// for other DB drivers so this won't affect them)
			/// Row prefetching uses a bit of memory but saves a ton
			/// of network latency. With current AdoDB and PHP, only
			/// Oracle uses this setting.
			define ('ADODB_PREFETCH_ROWS', 1000);
			break;
		default:
			/// if we have to lowercase it, set to 0
			/// - note that the lowercasing is very expensive
			define ('ADODB_ASSOC_CASE', 0); //Use lowercase fieldnames for ADODB_FETCH_ASSOC
	}
}

function init_memcached() {
	global $CFG, $MCACHE;

	include_once($CFG->libdir . '/memcached.class.php');
	$MCACHE = new memcached;
	if ($MCACHE->status()) {
		return true;
	} 
	unset($MCACHE);
	return false;										   
}

function init_eaccelerator() {
	global $CFG, $MCACHE;

	include_once($CFG->libdir . '/eaccelerator.class.php');
	$MCACHE = new eaccelerator;
	if ($MCACHE->status()) {
		return true;
	} 
	unset($MCACHE);
	return false;
}



?>
